Rick's Free Auto Repair Advice

Posts Tagged: fuel trim

What is fuel trim?

Fuel trim and what it means Engine computers use fuel trim to attempt to regulate the right amount of fuel to achieve maximum power, fuel mileage while also minimizing emissions. So they try to maintain a 14.7:1 ratio. If the engine were stationary, like on an engine stand, and you ran it at a fixed RPM it wouldn’t be hard to come up with a fuel flow to maintain consistent power and emissions. But that doesn’t happen in the real world. You’re always going up or down a hill, driving … Read More

Fuel Trim

What is fuel trim? Modern automotive computers use fuel trim to vary the amount of fuel provided to the engine based on a FEEDBACK STRATEGY to accommodate wear and tear on the engine components and sensor degradation. In other words, the computer receives feedback information from many different sensors to inform the computer how good of a job it did in calculating how much fuel to add to the incoming air. The computer then adds or subtracts fuel during the next injection cycle and reviews the feedback data again, so … Read More


Custom Wordpress Website created by Wizzy Wig Web Design, Minneapolis MN